SAN DIEGO — We’re sure your pets are marvelous, talented creatures; we’d never take that away from you.
But no, experts say, Fido and Fluffy cannot predict earthquakes.
At least, “not that we understand,” adds Sue Hough, a seismologist with the U.S. Geological Survey. “Because there’s a lot we don’t understand about earthquakes.”
In a phone interview this week, Hough told FOX5SanDiego.com she’s no stranger to seemingly convincing tales of animals “sensing” major quakes before they strike. Such stories date back to Greece in 373 BC, when historians say “rats, weasels, snakes, and centipedes reportedly left their homes and headed for safety several days before a destructive earthquake.”
But while “anecdotal evidence abounds,” researchers have not widely documented consistent and reliable behavior from animals that proves they predict earthquakes. Scientists aren’t sure how that would even work.
So how did this idea become so common? Hough said a few factors are at play, including a form of “selection bias” that leads people to draw conclusions from data that suits them. After a quake, people toss out other information in favor of the experience that supports their hunches.
Hough offered an example: After an earthquake, a number of people look back and say their cat acted bizarre the night prior for no apparent reason.
“The problem is, if you own a cat, you know they frequently act bizarre for no apparent reason,” the seismologist said. So, naturally, before an earthquake: “Some number of cats were acting bizarre for no apparent reason.”
But other factors driving this perception stand on firmer scientific ground.
While critters don’t — as far as we know — sense quakes before they get started, they are more sensitive to smaller shakes deep within Earth’s crust.
An earthquake with a magnitude of less than 3 won’t likely register for someone sitting at their kitchen table, but “a horse on four legs or a rabbit close to the ground” might sense it, Hough said. About half of major California earthquakes come with foreshocks, according to the seismologist, so your pet might feel some minor shaking before the main event.
But Hough said that’s different from prediction. Animals are not sensing something before it’s present, they’re simply experiencing something in real-time that you can’t feel.
And it’s not innate to their animal nature: Hough mentioned a case in which a chair leaned against a wall tumbled to the floor shortly before a major earthquake. The chair didn’t predict the quake and topple over in fear — it was knocked over by a foreshock that people in the room couldn’t perceive.
Can people predict earthquakes?
It’s not just our pets that lack seismographic clairvoyance.
“Neither the USGS nor any other scientists have ever predicted a major earthquake. We do not know how, and we do not expect to know how any time in the foreseeable future,” the agency’s website rather bluntly states.
“Earthquakes might be fundamentally unpredictable,” Hough said. “It’s not like weather. You can see weather patterns brewing. Whatever’s going on in the crust … we can’t really observe it directly.”
But scientists aren’t completely in the dark.
Earthquake Warning California, a first-of-its-kind statewide early warning system, can now give people a few seconds’ notice of major shaking to come. That’s just enough time to “drop, cover and hold on,” potentially saving people from serious injury or death.
Scientists tuned the system to alert residents at magnitudes of 4.5 or higher.
Similar to animals (or chairs) experiencing foreshocks, the system doesn’t predict anything that hasn’t already started, Hough explained. Instead, very sensitive instruments detect the fastest-moving waves caused by a rupturing fault, alerting residents before shaking starts on the surface.
The California Office of Emergency Services has a more detailed explanation if you’re curious.
The early warning system is your best bet for a heads up before the next major earthquake. Android phones come with the technology built-in, while iPhone users can download MyShake here.
Keep an eye on the app, but you don’t need to take cover the next time your pet is acting odd. That’s probably just the way they are.